diff --git a/packages/core/README.md b/packages/core/README.md
index 08ec495f..d42c2fc3 100644
--- a/packages/core/README.md
+++ b/packages/core/README.md
@@ -232,7 +232,6 @@ async function getIDTokenAction(): Promise<void> {
    if (audience !== undefined) 
       aud = `${audience}`
    const id_token = await core.getIDToken(aud)
-   const val = `ID token is ${id_token}`
    core.setSecret(id_token)
    core.setOutput('id_token', id_token)
       
diff --git a/packages/core/__tests__/core.test.ts b/packages/core/__tests__/core.test.ts
index 20ebbccf..5341383f 100644
--- a/packages/core/__tests__/core.test.ts
+++ b/packages/core/__tests__/core.test.ts
@@ -2,6 +2,7 @@ import * as fs from 'fs'
 import * as os from 'os'
 import * as path from 'path'
 import * as core from '../src/core'
+import * as oidcUtil from '../src/oidc-utils'
 var httpclient = require('@actions/http-client')
 
 /* eslint-disable @typescript-eslint/unbound-method */
@@ -394,6 +395,19 @@ function getTokenEndPoint() {
 }
 
 describe('oidc-client-tests', () => {
+  
+  const OLD_ENV = process.env
+  const oidcClient = new oidcUtil.OidcClient()
+
+  beforeEach(() => {
+    jest.resetModules() 
+    process.env = { ...OLD_ENV }; 
+  });
+
+  afterAll(() => {
+    process.env = OLD_ENV; 
+  });
+
   it('Get Http Client', async () => {
     const http = new httpclient.HttpClient('actions/oidc-client')
     expect(http).toBeDefined()
@@ -404,4 +418,25 @@ describe('oidc-client-tests', () => {
     const res = await http.get(getTokenEndPoint())
     expect(res.message.statusCode).toBe(200)
   })
+
+  it('check if success status return true, if succeeded', () => {
+    expect(oidcClient.isSuccessStatusCode(200)).toBeTruthy()
+  })
+
+  it('check if success status return false, if failed', () => {
+    expect(oidcClient.isSuccessStatusCode(400)).toBeFalsy()
+  })
+  
+  it('check if we get correct ID Token Request url with correct api version', () => {
+    process.env.ACTIONS_ID_TOKEN_REQUEST_URL = "https://www.example.com/"
+    expect(oidcClient.getIDTokenUrl()).toBe("https://www.example.com/?api-version=" + oidcClient.getApiVersion())
+  })
+
+  it('check if invalid json throws error', () => {
+    expect(() => oidcClient.parseJson("{}")).toThrow()
+  })
+
+  it('check if invalid json throws error', () => {
+    expect(oidcClient.parseJson('{"value" : "abc" }')).toBe("abc")
+  })
 })
\ No newline at end of file
diff --git a/packages/core/src/oidc-utils.ts b/packages/core/src/oidc-utils.ts
index f9b95e6c..ebabf946 100644
--- a/packages/core/src/oidc-utils.ts
+++ b/packages/core/src/oidc-utils.ts
@@ -68,8 +68,6 @@ export class OidcClient implements IOidcClient {
       throw new Error(`Failed to get Httpclient `)
     }
 
-    debug(`Httpclient created ${httpclient} `) // debug is only output if you set the secret `ACTIONS_RUNNER_DEBUG` to true
-
     let additionalHeaders: IHeaders = {}
     additionalHeaders[actions_http_client.Headers.ContentType] = actions_http_client.MediaTypes.ApplicationJson
     additionalHeaders[actions_http_client.Headers.Accept] = actions_http_client.MediaTypes.ApplicationJson
@@ -78,13 +76,13 @@ export class OidcClient implements IOidcClient {
 
     const data: string = audience !== null ? JSON.stringify({aud: audience}) : ''
     const response = await httpclient.post(id_token_url, data, additionalHeaders)
+    const body: string = await response.readBody()
 
     if (!this.isSuccessStatusCode(response.message.statusCode)) {
       throw new Error(
-        `Failed to get ID Token. Error Code : ${response.message.statusCode}  Error message : ${response.message.statusMessage}`
+        `Failed to get ID Token. \n Error Code : ${response.message.statusCode}  Error message : ${response.message.statusMessage} \n Response body: ${body}`
       )
     }
-    let body: string = await response.readBody()
 
     return body
   }